hallas



- J. G. HALLAS & J. N. WEBB.

' Chuck for Metal Lathes.

' No. 197,359. Patented Nov. 20, I877.

rwenor aw @iddm IL- FUERS mumoaawnsm WASHINGTON. D Cv To all whomit may concern tion and claims.

wnn-n or WATERB'URY, eonNECfrIoUr;

Specification forminglpart of LettersPateil-t No. 197,359, dated November 20,1877; ap neaudnniea s a April 21, 1877. it

Be it known thatywe, JAMES G.HhLLns and JAMES N. WEBB, both of Waterbury, in

the county of New Haven and State of Gonnecticut, have invented; a new Improvement in Adjustable Chucks; and we do hereby declare the following, when taken in connection with the accompanying drawings andt-he letters'of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawingsyconstitute part-of this specification, and represent, ini .Figure 1, a

its moving mechanism.

This invention relates to an improvement in chucks for lathes and like purposes.

In the usual construction of this class of tools the three jaws are arranged for a radial movement, and so combined that all must move simultaneously and to the same extent; but it frequently occurs that it is desirable to adjust the jaws independently of each other.

' The object of this invention is to provide each jaw with an adjustment independent of that which is common to all the jaws; and it 1 consists in combining, with the mechanism which simultaneously moves all the jaws, an

independent mechanism for each jaw, so that the jaws may be-moved simultaneously, or

a each independent of the other, and as more particularly recited in the following specifica- A represents the shell or head, on the'surface of which, in suitable grooves, the three radial jaws B are arranged so as to move a freely radially to or from the center. Within the shell a bevel-wheel, G, is arranged to revolve freely and concentric with the centerof' the chuck. Each jaw'is providedwiththe moving spindle D, its inn er end screw-threaded into an arm,E, extendingfromthe'jaws each of these spindles is a bevel-pinion, F, working in the bevel-gear 0; hence, bytu'rning the spindle D, thegear G. will "spondingly turned, and all the screws turned,

be correto move the respective jaws radially, and in substantially the usual manner.

Around each of the spindles D is 'a sleeve,

1 G, arranged intheedge of the shell,as seen perspective view, and in Fig. 2. alongitudinal section, :of one of the jaws and an adjustment the spindle in Fig. 2, and so as to be turned freely inde- I pendent of the spindle D, and yet held firmly from axial movement. Internally, this sleeve G is screw-threaded, and on the js'pin dle a second sleeve, a, is arranged, its exterior thread corresponding to the internalthread of the sleeve G, and this second sleeve, is arranged between shoulders on the spindle, and is prevented from turning by a flat-side taking a scan, at d, on the corresponding surface on the she 1. I

The. spindle may turn freely within this shell a. i

The pinion is fitted to the spindle so that, while it will turn the spindle,it will'allow the spindle to move axially without turning the pinion; hence, by turning the sleeve G, the sleeve a will be moved correspondingly in an axial direction, carrying with it the spindle D, and the jaw connected thereto, thus ena: bling the movement of each jaw independent of the others, n

It will be .understood that theouterfend of the sleeve G is constructed with convenient means for turning the same. (Here represented as of polygonal form.) I

By this construction it will be seen that while the jaws may be all moved simultaneously, by simply turning one of the spindles D, either may be adjusted independently ofthe other by turning the sleeve G on the spindle of the jaw which is to be adjusted. In such will slide freely through the pinion without changing the position of the pinion. I

In the usual construction, the workv rests upon the surface of the-jaws, and as this surface is liable to wear or vary from use, it soon follows that the true level bed desirable cannot be had.. To take this bed or bearing from the jaws, there is arranged on theface of the chuck, and a bearing, H, each having a surface or surfaces slightly above the face of the jaws, as seenin Fig. 1; hence the work will rest on the surface of these bearings,and the jaws will move without the face coming in contact with the work. a

It is not essential that all the jaws have this independent movement, as in some cases preferably each side of the jaws,

one only may have this independent movementybut it is desirable, for convenience, thatit be applied toall. I

We do not broadly claim a chuck having radially-moving jaws combined with mechanism to simultaneously move all the jaws, orto.

move independently either of the jaws, as such, we are aware, is not new.

We claim- 1. The combination of the radially:moving jaws, a screw-spindle for each jaw, a pinion on each spindle, a gear to connect all said pinions, an externally screw-threaded sleeve,

substantially as described.

JAMES G. HALLAS. v JAMES'NLWEBB.

Witnesses: GEORGE W. R0021, BENJAMIN HALLAS. 

